What is the CVSS score of CVE-2026-21634?

CVE-2026-21634 has a CVSS 3.1 base score of 6.5 (Medium). CVSS vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. EPSS exploitation probability: 0.0%.

Which versions of Unifi Protect are affected by CVE-2026-21634?

CVE-2026-21634 presents notable security risk, a buffer overflow vulnerability rated CVSS 6.5. Exploitation could cause memory corruption or application crashes.

How to fix or mitigate CVE-2026-21634?

Within 30 days: Identify affected systems and apply vendor patches as part of regular patch cycle. Monitor vendor channels for patch availability.

Unifi Protect CVE-2026-21634

MEDIUM

Buffer Overflow (CWE-119)

2026-01-05 support@hackerone.com

Buffer Overflow Unifi Protect

6.5

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

6.5 MEDIUM

AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector

Adjacent

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Lifecycle Timeline

Analysis Generated

Mar 12, 2026 - 21:54 vuln.today

CVE Published

Jan 05, 2026 - 17:15 nvd

MEDIUM 6.5

DescriptionCVE.org

A malicious actor with access to the adjacent network could overflow the UniFi Protect Application (Version 6.1.79 and earlier) discovery protocol causing it to restart.

Affected Products: UniFi Protect Application (Version 6.1.79 and earlier).

Mitigation: Update your UniFi Protect Application to Version 6.2.72 or later.

AnalysisAI

UniFi Protect Application versions 6.1.79 and earlier suffer from a buffer overflow in the discovery protocol that allows adjacent network attackers to trigger denial of service by causing the application to restart. The vulnerability requires network proximity but no authentication or user interaction, making it exploitable by any attacker on the same network segment. Administrators should upgrade to version 6.2.72 or later to remediate this issue.

Technical ContextAI

Classified as CWE-119 (Buffer Overflow). Affects Unifi Protect. A malicious actor with access to the adjacent network could overflow the UniFi Protect Application (Version 6.1.79 and earlier) discovery protocol causing it to restart.

Affected Products: UniFi Protect Application (Version 6.1.79 and earlier).

Mitigation: Update your UniFi Protect Application to Version 6.2.72 or later.